The invention relates to manufacture of a polymer based polishing pad, particularly a polishing pad used for polishing semiconductor substrates.
U.S. Pat. No 6,099,954 discloses a known method of manufacturing a polishing pad for polishing semiconductor substrates, includes the step of; coagulating a layer of viscous polishing material in-situ, meaning, directly onto, a portion of the manufactured polishing pad. The polishing material is an elastomer or polymer that is coagulated and dried, in situ, on a backing layer in sheet form. The polishing material solidifies and adheres to the backing layer. Prior to the invention, batch processing was performed to manufacture a limited number of polishing pads. The polishing pads that were manufactured by one batch processing varied from those manufactured by another batch processing. A need exists for a manufacturing process that avoids variations in polishing pads that are manufactured according to different batches.
The invention provides a continuous manufacturing process, which eliminates batch processing and reduces variations among polishing pads that are manufactured according to different batches. A method of manufacturing a polishing pad that is used for polishing a semiconductor substrate, comprises the steps of; transporting a continuous material forming a transported backing layer through successive manufacturing stations, supplying a fluid phase polymer composition onto the transported backing layer, shaping the polymer composition on the transported backing layer into a surface layer having a measured thickness, curing the polymer composition on the transported backing material in a curing oven to convert the polymer composition to a solid phase polymer layer attached to the transported backing layer, the solid phase polymer layer providing a solid phase polishing layer of a polishing pad that is used for polishing semiconductor substrates.